DeepSeek V4 Flash (free) is free for input tokens while Qwen3.5-9B costs $0.04 per 1M tokens.
API cost decision in 10 seconds
Qwen3.5-9B vs DeepSeek V4 Flash (free)
Pick DeepSeek V4 Flash (free) when budget and context both matter.
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Data confirmed:
Prices normalized to USD per 1M tokens
Sample workload: 1M input + 500K output
Budget verdict
Pick DeepSeek V4 Flash (free) when budget and context both matter.
On the standard 1M input plus 500K output workload, DeepSeek V4 Flash (free) is estimated at $0 vs $0.11 for Qwen3.5-9B, saving $0.11 (100% lower).
Cost-first pickDeepSeek V4 Flash (free)
Context-first pickDeepSeek V4 Flash (free)
Sample savings$0.11100%
10x traffic gap$1.15
DeepSeek V4 Flash (free) is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $1.15. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
DeepSeek V4 Flash (free) stays cheaper across input-heavy, balanced, and output-heavy sample workloads.
| Workload shape | Token mix | Better pick | Qwen3.5-9B | DeepSeek V4 Flash (free) |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | DeepSeek V4 Flash (free) | $0.28 | $0 |
| Balanced workload | 1M input + 1M output | DeepSeek V4 Flash (free) | $0.19 | $0 |
| Output-heavy chatbot | 1M input + 5M output | DeepSeek V4 Flash (free) | $0.79 | $0 |
DeepSeek V4 Flash (free) is free for output tokens while Qwen3.5-9B costs $0.15 per 1M tokens.
DeepSeek V4 Flash (free) has 786.43K more context (4x larger).
DeepSeek V4 Flash (free) is free for the standard workload while the other model is estimated at $0.11.
Estimate your workload cost
Your Workload Cost
This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.
Quick Decision
DeepSeek V4 Flash (free) has the lower input price; DeepSeek V4 Flash (free) has the lower output price; DeepSeek V4 Flash (free) offers the larger context window. For the 1M input plus 500K output sample, DeepSeek V4 Flash (free) is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $0.11 for Qwen3.5-9B and $0 for DeepSeek V4 Flash (free).
Choose Qwen3.5-9B when its provider, model quality, latency, or availability is more important than the numeric price/context winner.
Choose DeepSeek V4 Flash (free) when you care most about lower input-token price, lower output-token price, and larger context window.
- On the standard 1M input plus 500K output workload, DeepSeek V4 Flash (free) is estimated at $0 vs $0.11 for Qwen3.5-9B, saving $0.11 (100% lower).
- DeepSeek V4 Flash (free) is free for the standard workload while the other model is estimated at $0.11.
- DeepSeek V4 Flash (free) is free for input tokens while Qwen3.5-9B costs $0.04 per 1M tokens.
- DeepSeek V4 Flash (free) is free for output tokens while Qwen3.5-9B costs $0.15 per 1M tokens.
- DeepSeek V4 Flash (free) has 786.43K more context (4x larger).
| Feature | Qwen3.5-9B (Qwen) | DeepSeek V4 Flash (free) (DeepSeek) |
|---|---|---|
| Input Price prompt tokens per 1M | $0.04 | $0 |
| Completion Price per 1M tokens | $0.15 | $0 |
| Sample Workload Cost 1M input + 500K output | $0.11 | $0 |
| Context Window | 262.14K | 1.05M |
| Release Date | ||
| Popularity | #61 | #78 |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | DeepSeek V4 Flash (free) | On the standard 1M input plus 500K output workload, DeepSeek V4 Flash (free) is estimated at $0 vs $0.11 for Qwen3.5-9B, saving $0.11 (100% lower). |
| High-volume input processing | DeepSeek V4 Flash (free) | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | DeepSeek V4 Flash (free) | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | DeepSeek V4 Flash (free) | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- Qwen3 Next 80B A3B Instruct (free) can replace Qwen3.5-9B when lower sample workload cost matters most: $0.
- Qwen3 Coder 480B A35B (free) can replace Qwen3.5-9B when lower sample workload cost matters most: $0.
- Qwen2.5 7B Instruct can replace Qwen3.5-9B when lower sample workload cost matters most: $0.09.
- Owl Alpha offers 1.05M context with $0 sample workload cost.
- DeepSeek V4 Flash · DeepSeek · #1
- Hy3 preview · Tencent · #2
- Claude Opus 4.7 · Anthropic · #3
- Claude Sonnet 4.6 · Anthropic · #4
Cheaper alternatives
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Open DeepSeek modelsQwen3.5-9B is a multimodal foundation model from the Qwen3.5 family, designed to deliver strong reasoning, coding, and visual understanding in an efficient 9B-parameter architecture. It uses a unified vision-language design...
DeepSeek V4 Flash is an efficiency-optimized Mixture-of-Experts model from DeepSeek with 284B total parameters and 13B activated parameters, supporting a 1M-token context window. It is designed for fast inference and...